Automatic circuit breaker



Nov. 4

M. HERTZ AUTOMATIC CIRCUIT BREAKER Filed Feb. 24

" P Y El v @11mm l-muli Patented Nov. 4, 1924.

UNITED STATES MICHAEL HERTZ, OF NEWARK, NW JERSEY.

AUTOMATIC CIRCUIT BREAKER.

Application led February 24, 1921.

To @ZZ whom t may concern:

Be it known thatA I, MICHAEL Hnirrz, a citizen of the United States,residing at Newark, in the county ot Essex, State oi New Jersey, haveinvented certain new and useful Improvements in Automatic CircuitBreakers, of which the following is a description, reference being hadto the accompanying drawing and to the figures of reference markedthereon.

This invention relates to electromagnetically controlled circuitbreakers wherein a solenoid in series with the load is adapted to tripthe breaker upon excessive load or upon short circuit and wherein it isimpossible for the operator to maintain the circuit breaker closed aslong as the excessive load or short circuit exists.

It is a particular object of my invention to form a neat, compact switchadaptable for mounting on the dashboard of an automobile, although itmay be used in other relations.

It is another object of my invention to make a device of this characteras oi few parts and as cheap as possible.

Other objects will appear after reaching the specification and claims inconnection with the accompanying drawings, in which:

Figure 1 is a central longitudinal section through my circuit breakerwith the circuit breaker in closed position.

Figure 2 is an end view thereof, with the end wall, adjacent the switch,removed.

Figure 3 is a section along the line 3 3 of Figure 1, the circuitbreaker, however, being shown open.

Figure 4 is a view showing the position of parts just after the coil hasbeen energized so as to withdraw the latching rod, the circuit breakerbeing tripped, and the latching rod being urged to its uppermostposition.

Figure 5 is a view showing the normal relationship of parts, the circuitbreaker being open.

Figure 6 is a plan view of the casing of the circuit breaker, thecovering being removed, and

Figure 7 is a circuit diagram of the system including my circuitbreaker.

Now referring to the drawings more in detail, 1 is a casing ot mouldedmaterial such as bakelite, americanite or the like embedded in which isapair of contacts 2 and Seriali No. 447,425.

ing and being provided with a terminal nut 4. The other contact 3 isprovided with a terminal 5 within the casing to which is secured as by ascrew 6 alead 7 of a solenoid 8, the other lead 10 of which is groundedinto the metallic case 9 of the solenoid as by means of baring the wireat the point where it emerges from the casing and soldering it theretoas at 11. The lead 10 is secured to a terminal 12 in the bottom of thecasing 1. The leads 7 and 10 are purposely made long so as to permit thesolenoid to be removed from the casing 1 for inspection withoutdisconnecting the lead wires from the terminals.

The solenoid is wound on a square hollow brass core 18, a suitable fibreinsulator 14 being interposed between the windings and the metalliccore. At one end the solenoid is provided with a sott iron core 15provided with a stem 16 adapted to pass through a metallic insert 17moulded into the casing and to be secured to the casing by means of anut 18 and a suitable lockwasher. To securely hold the solenoid in placethe metallic case 9 is spun over the coil and a washer 19 is interposedbetween the enlarged core portion 15 and the case 9, thereby causing thecase 9 to be firmly wedged against the wall of the casing 1 when the nut18 is tightened.

Slidable within the brass core of the solenoid is a soft iron squareplunger 2O urged outwardly by a coil spring 21 made of nonmagneticmaterial such as brass. Slidable in the outer end oi' the iron plungeris a circular latch rod 22 of some suitable insulating material such asfibre provided with a collar 23 and a shouldered portion 24, and aspring 25 is interposed between the collar 23 and the plunger 2O to urgethe rod to the position shown in Figures 4 and 5. A stop pin 26 limitsthe upward movement of the latch rod while a dog 27 moulded into thecasing 1 maintains the rod in latched position when the circuit breakeris in the position shown in Figure 1.

The latch rod co-operates with a square switcn rod 28 j ournaled forreciprocal movement in the bottom of the casing, the casing beingsuitably provided with a square hole 29 which may be hushed it desired.The switch rod is urged upwardly to the position shown in Figures 3, 4and 5 by means 55s-end connected with a terminal 48 in. the

of a spring 30 and the upward motion is limited by a stoppin 31passing'through ythe rod. Thielupper'end of the switch rod carries aspring blade contact 32 adaptedv to bridge the contacts 2 and 3, whenthe switch rod is in the depressed position shown in Figures 1 and 2.

Secured to the casing l is a cover plate 43 conveniently made ofy apunched metallic piece provided with two cup shaped depressions 33,aiid34. Seated in each oithese depresjsions` is` a spring-.35 and 36, respeotively,l whichv tends tov maintain a resetting push button. S'randk acircuit breaker tripping button 38 -in extruded posi-tiomtheoutwardlimit of motion oit t-liese buttonsbeing tixedibybthe stoppinsitl4 and 4O,passing through the AShanks of the buttons. The shank 4lof the push button 37 is of such a length. as to justl clear the( rod 22in its elevated positiom whilethe shank 42 of the push button 38extendsto apoint slightly above.; the grounded case 9 of the solenoid.Thecoyerfplate is securedto the casing by =meansoftwo screwsr44tappedinto. an iiisert 45 moulded in the casing and into a prolongation ot thedog 27 already described., The dogmayconveniently be made of'an extrudedbarhaving the cross section @shown in Figure, l and cut oft intov piecesof convenient,length.l A lead 46has one end clamped,.betweenthe coverlplate and a cut outportion4"(` of the casing l'to make elec,`tricalcontlctwith, the, cover, and the other bottomxothe casing..Theterminals 4 and 48y areadapted lto be connected to oppositeA sidesof`a source ofcurrent such as a battery B while the terminal l2 is adaptedto' be connecteduwitli the load L, the opposite ter7 minal of thelloadvgbeing yconnected to that v side of the source of current Bfwhichis in '55s released. Upon short circuit or excessive electricalconnection with the. terminal 48.

Vlith. the circuit breaker open, the parts areas shown in Figure5. Whenit is desired yto, close. the. circuit, the push ybutton 37 is depressedvand the motion thereof-istransmitted through thelatch rod- 22 toV theswitch'rod 28. When, 1the latchA rod 22 has4 tbeensuiiicientlydepressed,the spring 2l in thesolenoid urges Vtherod122. to the left in Figure5,4, thereby causing the shouldered portion of the rodto lengageunderneath the dog The push button 3;? may now be kthe coil 8 whichmomentarily shortcircuits the load L to permit the coil to be energizedsuiiiciently to pullrin the plunger 20, to thereby trip the switch.

I have thus provided a neat, compact mechanism for automaticallytripping the circuit under predetermined conditions, all ot which isencompassed within a casing` ot relatively small dimensions, the circuitbreaker being non-settable under conditions of overload or shortcircuity Having thus `described my invention what l claim is:

l. In an automatic circuit breaker, a longitudinally movable. switch, alongitudinally movable rod in alignment therewith but spaced therefrom,an electromagnet in series with the circuit breaker, a member controlledby said electromagnet and movable in a plane at right angles to theline. of movement of the switch and rod interposedbetween the rod andthe switch, said member being' normally mechanicallyheld in vline totransmit a mechanical `torce from the rod to the switchy but operable,under excessive load conditions, to break the continuity of the line. i

2. In an automatic circuit breaker,a recip- 100 rocable switch memberprovided with resilient means to urge it to open position, a push rodiii alignment therewith butspaced therefrom, a movable rod interposed:between the switch member and the push rod and inrod to another of itspositions when-released V from said retaining means, and electromagneticmeans in series with the circuit breaker to move the movable rod out ofVengagement with the retamingmeans and out ol-aligib `ment with the pushrod and switch member when suticiently energized.y

3. In an auto-matic circuit breaker, a lonf gitudinally reciprocableswitch, a i rod in. alignment therewith but spaced therefrom, a memberinterposed between the rod and the switch, lan electromagnetVcontrolling the same, said member being normally mechanically held inline to transmit a mechanical force from the rody to the. switch when`the electromagnet is insutliciently energized-buty operable, underpredetermined conditions, to break the. continuity of the line,- and asecond rod Substantially parallel to the iirst and under control of theoperator `for trip yping the switch to open .position 4. In an automaticcircuit breaker, alongitudinally movable switch, a longitudinallymovable rod in alignment therewith but spaced therefrom, anelectromagnetically controlled member', movable in planes at rightangles to and parallel with the line of movement of the switch and rodinterposed between the rod and the switch, said member being normally inline to transmit a mechanical force from the rod to the switch butoperable, under predetermined conditions, to break the continuity of theline, and a second longitudinally movable rod for the circuit breakerunder control of the operator for closing a circuit through saidelectromagnet for tripping the switch to open position.

5. In an automatic circuit breaker, a reciprocable switch and areciprocable rod movable in alignment therewith but spaced therefrom, anelectromagnetically controlled intermediate member normally mechanicallyretained in alignment with said switch and rod to transmit a mechanicalforce from the rod to the switch, said member being bodily movable in asubstantially rectangular path to accommodate itself to the position ofthe switch in either open circuit or closed circuit position and tobreak the line of transmission of force under predetermined conditions,and a second reciprocal rod for the circuitl breaker under control ofthe operator for tripping the switch to open position.

6. In an automatic circuit breaker, a reciprocable switch, alongitudinally and laterally movable rod in alignment therewith,latching mechanism for restraining the rod in switch closing position,electromagnetically operated means for moving the rod laterally topermit the switch to be opened, and resilient means for urging said rodlongitudinally toward switch resetting position when released from saidlatching mechanism.

7. In an automatic circuit breaker, a reciprocable switch, alongitudinally and laterally movable rod in alignment therewith,latching mechanism for restraining the rod in switch closing position,electromagnetically operated means in series with the circuit breaker ormoving the rod laterally to permit the switch to be opened, andresilient means for urging said rod longitudinally and laterally towardswitch resetting position when released from said latching mechanismafter the circuit breaker has been opened.

In testimony whereof, I affix my signature.

MICHAEL HERTZ.

